$datum= "17-11-2022";
echo date("t-m-Y", strtotime($datum)). "<br>";

$date = new DateTime('17-11-2022');
$date->modify('last day of this month');
echo $date->format('d-m-Y'). "<br>";
echo cal_days_in_month(CAL_GREGORIAN, 11, 2022). "<br>";